1. Field of the Invention
The present invention relates to a process for efficiently producing L-aspartic acid from fumaric acid or a salt thereof and ammonia or an ammonium salt as starting materials, by utilizing the reaction of an enzyme present in an aerobic culture of a microorganism belonging to the Genus Brevibacterium and having resistance to .alpha.-amino-n-butyric acid.
2. Description of the Prior Art
L-Aspartic acid is known to be present in protein as one of the important amino acids, and is used in medicines and as a food additive.
Heretofore, it has been known that aspartase, which can be obtained from cells of Escherichia coli, is an enzyme which dominates the reaction to form L-aspartic acid from fumaric acid and ammonia. More recently, methods have become known for producing L-aspartic acid from fumaric acid and ammonia by a fermentation culture method using various microorganisms.
In the conventional fermentation culture method, L-aspartic acid is produced from fumaric acid and ammonia using aspartase in microorganisms, and therefore it has been an important factor for production on a commercial scale to obtain microorganisms having strong aspartase activity; however, separation of microorganisms which satisfy such purposes from nature is accompanied by many difficulties, thus inhibiting the industrial use of such methods.